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Obtaining Raw Materials. Exploring Manufacturing Chapter 6. After studying this chapter, you will be able to:. Define renewable and exhaustible resources and give examples of each. Describe three different methods for mining raw materials.
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Obtaining Raw Materials Exploring Manufacturing Chapter 6
After studying this chapter, you will be able to: • Define renewable and exhaustible resources and give examples of each. • Describe three different methods for mining raw materials. • Define and describe two methods of drilling for oil and gas. • Describe three methods of harvesting forests. • Explain methods by which raw materials are moved to mills and refineries.
Raw materials • Raw materials are natural resources found on or in the earth or seas. • All manufacturing starts with raw materials. • These materials are of two basic types, they are renewable or exhaustible.
Renewable Trees Cotton Wool Flax Animal hides Exhaustible Metal ores Petroleum Natural gas Coal Clays Resources
RENEWABLE RESOURCES • Renewable resources are biological materials (growing things). • Each growing unit (plant or animal) has a life cycle. • First, it is planted or born. • It then grows through stages to maturity (full size). • Finally, it becomes old and dies.
Good Example: a tree • It is planted by nature or people. • It grows and, after a number of years, reaches full size. • Then, growth slows and finally stops. • Limbs die and fall off. • Insects, wind, and decay attack the tree. • In time, it dies and falls to the forest floor. • There it rots, providing nutrients (food) for other plants.
Managing Resources • Managing a resource means making sure that there is always a supply to use. • People must plan and work at growing new resources and knowing when and how to harvest them. • Example, a forester should not cut down all the trees in a forest without planting new ones.
EXHAUSTIBLE RESOURCES • Exhaustible resources have a limited supply. There is a fixed amount of them on earth. They can be used up. Like the dinosaurs, a material can become extinct. • For example, there is only so much petroleum, gold ore, natural gas, or iron ore on the earth. If we use them all up, that’s it. Thus, all resources must be used wisely.
Obtaining Raw Materials • Obtaining raw materials for manufacturing is a three-step process. This includes: • Locating resources • Gathering resources • Transporting (moving) resources.
LOCATING RAW MATERIALS • A large part of getting raw materials is finding them. • Aerial mapping – using an airplane to take pictures. • Geological – under the ground. • Geologists – people who study the structure of the earth. • Grown commercially for money • Trees • Livestock
GATHERING RAW MATERIALS • This is done using three major methods. • Mining • Drilling • Harvesting
MINING • Mining involves digging resources out of the earth. • Open-pit mining: a type of mining used when the resource is close to the surface. • Underground mining: a mining method that uses digging tunnels to reach the material. There are three major underground mining methods: shaft mining, drift mining, and slope mining.
Shaft Mining • This method is used for deeply buried mineral deposits. A shaft and an air shaft are dug down to the level of the deposit. The material is mined by digging horizontal tunnels from the vertical shaft.
Drift Mining • This method is used when the mineral vein comes to the surface at one point. A tunnel is dug into the vein, which is serviced by rail cars that move along the drift shaft.
Slope Mining • This method is used for a shallow mineral deposit. A sloping tunnel is dug down to the deposit. The minerals are often carried to the surface on a moving platform called a conveyor.
Drilling • A method used to reach underground liquid resources such as oil and water. A small round hole is drilled using a derrick and a drill bit that grinds up the rock as it drills.
Vertical Drilling • The most common type of drilling; the result is a hole that runs straight up and down.
Directional Drilling • A technique that allows wells to be drilled at an angle or along a curve to reach oil or gas.
Harvesting • Harvesting is a method used to collect a growing resource. Trees are the major “growing” resource that produce engineering materials. Trees are harvested using one of three methods. • Selective cutting • Clear-cutting • Seed tree cutting
Selective Cutting • A harvesting technique in that mature trees are selected and cut. Younger trees are left standing.
Clear Cutting • A method for harvesting trees that cuts down all trees regardless of age or species.
Seed Tree Cutting • All trees in an area, except for four or five large ones, are cut. The large trees reseed the area. This technique is used in the southern pine forests.
Harvesting • Harvesting requires several steps. • First, either trees or the area to be harvested must be selected. • Fallers then fell (cut down) the trees. • Bucker removes the limbs and top • The tree is cut to standard lengths for the mill. • The lengths, called logs, are moved to a central location for loading on trucks or railcars. This task is called yarding. • From the yard, the trees are hauled to the mill. • They are placed in a pond to help retain their moisture and reduce insect damage.
Transporting Resources • Nearly every type of land and water transportation is used to move raw materials. • Coal can be ground up and mixed with water, forming a slurry, for pipeline transport. • Trucks of all kinds and sizes move mineral and forest products. • Barges and ships are used on inland waterways and oceans. • In short, the most economical method is used to move raw materials from mine, well, and forest.
Summary • Raw materials are the foundation for all manufactured goods. • These materials are either a renewable or an exhaustible resource. • They are located, gathered, and transported to primary processing mills or refineries. • Commonly, raw materials are gathered through mining, drilling, and harvesting. • The gathered resources move over land and on water. • Then they are transformed (changed) into industrial materials.
Define renewable and exhaustible resources and give examples of each. • Renewable resources: • are biological materials (growing things). • Trees • Cotton • Wool • Flax • Animal hides • Exhaustible resources: • have a limited supply. There is a fixed amount of them on earth. They can be used up. Like the dinosaurs, a material can become extinct. • Metal ores • Petroleum • Natural gas • Coal • Clays
Describe three different methods for mining raw materials. • Shaft Mining • Drift Mining • Slope Mining
Define and describe two methods of drilling for oil and gas. • Vertical Drilling • Directional Drilling
Describe three methods of harvesting forests. • Selective cutting • Clear-cutting • Seed tree cutting
Explain methods by which raw materials are moved to mills and refineries. • Trucks of all kinds and sizes move mineral and forest products. • Barges and ships are used on inland waterways and oceans.